Use this task when you call an Enterprise
JavaBeans® (EJB) application that is deployed on WebSphere® Application Server for z/OS® from
an external address space within a client-initiated transaction.
Before you begin
Prior to version 8.0.0.4, the only environment where transactional
semantics are supported is Customer Information Control System (CICS®).
Starting with Version 8.0.0.4,
the Customer Information Control System (CICS®) and Information Management
System (IMS) are the only environments where transactional support
is provided with WOLA.
The client process must be running on
a z/OS operating system and the client environment must support transactional
semantics. The connection between the client and the WebSphere Application Server is configured
to support transactions. Also, the client must have called the Register
API with the TRANSACTIONAL flag set to the value of 1.
When running in an IMS dependent region, the
IMS environment must be running with RRS=YES.
About this task
This process starts when you begin a transaction in a client
environment. The client calls an EJB application that is running on WebSphere Application Server for z/OS and propagates
the new transaction to the application server. The semantics for starting
a transaction in the client environment varies based on the client
environment. Refer to the CICS documentation for information about
the semantics for starting a transaction in a CICS client environment. Refer to the IMS documentation for information
about the semantics for starting a transaction in an IMS client environment.
Procedure
- Deploy an EJB application on WebSphere Application Server. Use a transaction
attribute, such as required, support or mandatory, on the execute
method.
- Start a transaction on the client application using the
transactional semantics. The client application performs transactional
work that is required in the client environment.
- Use the Invoke (BBOA1INV) API or the Send Request (BBOA1SRQ)
API to make a remote call with the client program to the EJB application
that is deployed on WebSphere Application Server.
The transaction context propagates to the WebSphere Application Server server and the
EJB application runs under the transaction context.
- Use the transactional semantics of the client environment
to commit or end the transaction independent of the outcome of the WebSphere Application Server server transaction.
Results
The new transaction is propagated to the WebSphere Application Server for z/OS server.
The client commits the transaction and a single two-phase commit completes
the transaction across the two address spaces.